code: def frame(self):
      return self._frame
  
file_path: matplotlib/lib/matplotlib/testing/jpl_units/Epoch.py
imports: import functools
  import operator
  import math
  import datetime
  from matplotlib import _api
  from matplotlib.dates import date2num
label_desc: Use image node_id 3 for calling the Epoch obj's underlying member method code with example usage: obj.frame() and returns: self